Releasing grip trip



United States Patent This invention relates to a release device for a chain hoist.

The object of the invention is to provide a release device for a chain hoist which will facilitate the lifting,

transporting, storage and other handling of various materials such as sugar cane, lumber or the like.

Another object of the invention is to provide a release device for a chain hoist which includes a novel mechanism for releasing the device so that there will be no danger of the workmen being hurt by the load.

A further object of the invention is to provide a releasing chain sling grip trip for use as a material handling device whereby the operator of the crane or similar device will be able to release the load of material at will.

Another object of the invention is to provide a release device for a chain hoist which includes a single spring which is positioned or located so as to maintain suflicient pressure on the dog and latch whereby a weak or defective spring can be changed without the necessity of destroying all of the riveted pins.

A further object of the invention is to provide a releasing grip trip mechanism which is extremely simple and inexpensive to manufacture.

Other objects and advantages will be apparent during the course of the following description.

In the accompanying drawings, forming a part of this application, and in which like numerals are used to designate like parts throughout the same.

Figure 1 is a side elevational view illustrating the device in use and mounted on a chain or sling.

Figure 2 is an elevational view of the device with parts broken away and in section.

Figure 3 is a fragmentary elevational view illustrating one of the side plates.

Figure 4 is a plan view of the mechanism shown In Figure 2, and with the chain removed.

Figure 5 is a sectional view taken on the line 55 of Figure 2.

Figure 6 is a view similar to Figure 5 but illustrating a modified clamp.

Figure 7 is a perspective view illustrating the latch.

Figure 8 is a sectional view illustrating a modified form of releasing device.

Figure 9 is a plan view of the device shown in Figure 8.

Figure 10 is a sectional view taken on the line 10-10 of Figure '8.

Figure 11 is a sectional view taken on the line 11-11 of Figure 8.

Figure 12 is a sectional view taken on the line 12-12 of Figure 8.

Figure 13 is a sectional view similar to Figure 10 but illustrating a modification.

Figure 14 is a sectional view taken on the line 14-14 of Figure 5.

Referring in detail to the drawings the numeral 10 designates a chain, Figure 1, which may have a ring 11 attached to anend thereof. A disc or stop 12 may be mounted on the chain 10, and the ring 11 can be con- 2 ,903,292 Patented Sept. 8, 1959 nected to a member that is to be used for lifting a load such as a load of sugar cane, lumber or the like.

The present invention is directed to an article gripping mechanism 14 which includes a pair of spaced parallel plates 15 which may be made of any suitable material such as metal.

With the present invention the operator of a crane or similar device can release the load of material at will. Heretofore such devices have required one or more additional men depending on the load being handled to release the load independently of the crane operator. These men stand by in a .very hazardous position to release each grip trip singly, and loads that are released in the air require one man for each sling that are released simultaneously to prevent excessive breakage by overloading the remaining slings. By means of the present invention, the releasing dogs that trip the load can be readily actuated from a crane or derrick so that with the present invention, one, two or more chain slings can be released simultaneously by the operator of the crane, derrick, boom, or similar device so that it will not be necessary for an excessive load to be carried or borne by any one or more trips and also the hand trippers are eliminated. Also, the present invention will not hinder the operation of the manual release system now in use and the device can be made with a minimum amount of expense.

Extending between one end of the plates 15 is a first pin 16 which has a pulley or sheave 17 mounted thereon, and a portion of the chain 10 engages the sheave 17. Extending between the pair of plates 15 is a second pin 18 which has a dog 19 mounted thereon, and formed integral with the dog 19 is a thumb tab 20 and chain stop 21.

There is further provided a third pin 22, which extends between the plates 15, and a latch 23 is movably mounted on the pin 22. A latch 23 is provided with a cutout 24 that defines a pair of spaced apart fingers 25 for a purpose that is later to be described. A hook member 27 is movably mounted on a pin 26, and an end of the chain 10 is adapted to engage the hook member 27.

Extending outwardly from the latch 23 is a boss 28, and a coil spring 29 has one end connected to the boss 28, while the other end of the coil spring 29 is connected to a boss 30 on the dog 19.

Each of the plates 15 is provided with an upwardly extending portion 31, and each of the portions. 31 is provided with a slot or cutout 32, Figure 3. A clamp 33 includes a loop 34 which has a pairof straight portions 35 extended therefrom, and the straight portions 35 terminate in criss-cross portions 36 which each terminate in straight sections 37. The straight sections 37 terminate in inwardly extending aligned arms 38, and the arms 38 project through the slot 32. A suitable material such as the cable 39, Figure 1, is adapted to beconnected to the loop 34 of the clamp 33 whereby the clamp can be actuated from a suitable location such as the crane being used.

Referring to Figure 6 of the drawings there is shown a modified arrangement wherein there is provided a modified clamp which is indicated by the numeral 42, and the clamp 42 serves the same purpose as the previously described clamp 33. The clamp 42 includes a loop 43 which terminates in a pair of straight portions 44, and extending from each of the straight portions 44 is an olfset section 45 which terminates in a straight section 46, and the sections 46 terminate in outwardly projecting arms 47. The ends of the arms 47 may be movably 3 fingers "48 of the latch "49,and the latch 49 functions in the 'samemanner as the'previously described latch 23.

Referring to Figures 8 through 12 of the drawings,

there is shown a modified form of the device which is indic'ated'g'en'e'rally- -bytl1e ni1rn'eral' 50. The device 50 includesa pair -o'f-"spaced parallel pIates jS 1,- and a chain *Suchas the chain isadapted toen'gage a'curved'guide inember sa, and the :guide inernbe'r 53 serves the same purpose as'thepreviously described sheave 17. Extending between the pair of plates 51 is a pin 52 which has a pawl-or 'dog 54mou'nted thereon. Athumbtab 55 is 'provided" for actuating the -dog 54. E i'rte'n'ding between "the pairofplates 'fl' is'a block 56,- and-a bolt 59 serves to "secure the pairof spring membe'rs5 7 and 58 to theblock 56. "Abody member61is-movably mountedon a pin 60 which extends" between -the pair of plates 51, and the body m'ember' 61 isprovided with 'a-cut 'out62 as well as -a'cylindrical -cam portion 63. -A"-hook-member'64 is provided with a-leverportion 65 which extends 'into the cut out' '62, a'ndthe hook member 64 mounted on a pin '66. -Pr ojecting from the side-plates 51is a bracket 67, and portions of'the b'racket 67 -arespacedfrom'the top edgesof theside'wall soas-to define slots or cut outs'68 for 'erigagcmeht 'by arms "such -as the arms 38 of the clamp 33. f'Af brace or'stop member '69 may extend betwe'en-the-plates' 51-and 'rnay be secured thereto in'any 's uitable rnanner, as for 'example, by welding. V

R'eferrin'g to Figure13 of the drawings, there is shown -a-modifie'dforrnof the devic'e which is indicated generallyby thenum'eral70, andthe device 70 includes a pair of spaced parallel side plates 71 which may each be providedwith slots 72 for engagement by the arms 47 Fromthe foregoing, it is apparent that there has been provided a releasedevice for a chain hoist which is -especially suitable for-use in hoisting or otherwise handling -lo'ads of material such as sugar cane or lumber. In use, chains such as the chains 10 may be wrapped or t'rained around a load of material being handled, and

"then thering 11 'can'be' connected-to a-suitablehoist or crane by 'means of a hook, or the-like. The clamp, such 1 asthe clamp "33 can 'also be connected to the. crane by nre'ans of a normally slack cable 39, and with the parts arranged as shown in Figure 2 the gripping mechanism l 4=will lockthe chain ltl in its proper position on the loa'd. When it is 'desired torelease'the' chain 10, it is "only necessaryto apply tension to the cable 39. Pivotal 'rnovement-of thelatch 23 will free the hook member 27 so that the hook member 27 can pivot to permit disengagement of'the chain lll therefrom. At the same time, thedog 19 can be disengaged from the chain 10.

Thespring 29 tends' tomaintainthe'parts in their normally locked position.

Instead of usirrg the clamp33 shown in'Figures 1 "through 5, theclamp"42 canbe used. Thus, the clamp 3 42 includes'the"outwardly projecting 'arms"47 which are m'ovably-rnounted inilgrooves 41, so thatby pulling on the bl amp'42 by 'means of thecable 39, -the=arms' 47 will engagebeneath the fingers "48 of the latch 49' to thereby release; the'cha'in.

Referring now to Figures 8 through 12 of the drawings there is shown a still further modification wherein the chain 10 is again adapted to be wrapped ortrained *around al'oad of 'mater'ial' such as =logs,sugar cane or 'the like' 'and'the' clamp 33'may' be actuated by a crane 5 operator by means of -a suitable cable connected thereto.

To disengage orrelease the chain 10, it is only necessary to apply-pressure onthe clamp 33 by means of a cable such;-as the:cable 39 and thiswill pivot the body member 61, since the arms 38 will engage the cam portion 63 of the body member -61 when tension is applied to the clamp33. As "the body jinember 61pivots, the lever 65 will be free tojpivot on the pin 66 sothat that portion off'thechaimwhichengages thehook 64 can be disen- Tga'ged; Furthermor pressure can be applied manually on the tab 55 to pivot the pawl 54 so that the pawl can also be disengaged from the chain 10. The spring members 57 and 58 tend to maintain the parts in the position shown in Figure 8.

Instead of using the clamp 33 for actuating the body member 61, a clamp such as the clamp 42 shown in Figure 13 can be used. The clamp 42 has its outwardly projecting arms 47 slidably mounted in slots 72 in the side plates 71 of the gripping device 70.

With the present invention, a sling can be made using the chain It as shown in Figure 1 and with the device 14 attached thereto so that bundles of various materials suchas sugar cane can be readily moved as desired and such material can be handled safely and speedily.

In Figure 8, when the bundle is choked, the pawl 54 latches in the chain 10 and prevents loosening of the bundle even when the lifting load is relaxed. The thumb tab 55 can be used for retracting the pawl 54 to release the chain by striking the tab 55 with an iron bar, the hook 64 having been previously released by actuating the clamp 33. The link on the hook 64'falls clear of the hook when the body member 61 is moved by means of the clamp. The disc 12 acts as a stop. ringto limit movement of the chain in the device.

The release device for a chain hoist of the present in- -vention will quickly tighten the bundle and hold the load tightly and positively and the device is light in weight and strong and safe to use. The arms such as the arms 38 and the clamp 33 may have circularilanges 73 welded or otherwise secured thereto for limiting inward movement of the arms. The spring 29 serves to return the latch 23 and dog 19 to their proper position and also maintain the desired pressure thereon.

:It is to be understood that the releasing'mechanism of the present invention whereby the clamp is used to release the device, is highly advantageous since thedevice can be released without the necessity of having a person standing close by the assembly.

The link which is looped over the hook 27 is .identified by thenumeral 74, and as previously described, the dog 19 includes the thumb tab.20 and chain stop 21. The chain stop 21 of the dog 19 has the same width as the sheave 17. With the present invention, a single springis suitably located so as to maintain suflicient pressure on the dog and latch whereby a weak or defectivev spring can be changed without the necessity of destroying all of the riveted pins.

The operation of the device is as follows: Two or more chains are placed across the bottom of a cart, railroad flat car or truck with the releasing device 14 hanging over one side and the balance of the chain 10 over the other side. The material is located on top of the chain 10 and when completed the end link 74 is looped over the hook 27 and the chain 10 is pulled hand'taut-with the sheave 17 and dog- 19 preventing the chain'from loosening and the contents from flying out while being transported.

At the loads final destination the derrick 'or other suitablelifting device swings down'and the driver of the vehicle will hook the end ring 11 on to the spreader bar (a bar with evenly spaced hooks to accommodate the number of slings that may be used on each load), and pulls the quick acting clamp 33 from guide eyes on the spreader bar which acts as a guide for cable 34. The clamp 33 is squeezed by hand along the straightportions 35 which open the arms 38 and is arrangedirr engagement with the finger 25 which is a 'part. of the latch 23 and along the cutout 32 of the side plates 31. This operation is repeated for each sling used.

The operator of the hoisting device raises theload to any desired location and by applying pressure with the cable 39 which in turn pulls the clamp 33 free of' the grooves, and in so doing actuates the latch 23-which released the hook27 to thereby pivot' an'd disengage-the *link 74 so-that the load falls free. The-clamps'33 then ,rm R

immediately pull free of the trips 14 and return to the guide eyes of the spreader bar and are in position for the next load.

The spring 29 is attached to the dog 19 and latch 23 by bosses which may either be cast as part of the dog and latch or inserted later and these bosses are indicated by the numerals 28 and 30. Pressure is maintained by spring 29 on the cutout section of the hook 27 and keeps constant pressure through the chain stop 21 of the dog 19 on the chain which is free to tighten around the bundle but is prevented from loosening on the bundle by the dog 19.

The modified releasing mechanism shown in Figure 8 operates the same as the previously described device with the exception that the clamp 33 is inserted under the arm 67 and when the lifting operator actuates the releasing cable 39, the arms 38 of the clamp 33 move outward and engage the cam portion 63 with a rearward pressure to release the hook 64 so as to pivot and release the end of the chain and the load then falls free.

As shown in Figure 14, the plates may be provided with grooves 76 for receiving pins 75 and this pin and groove arrangement acts to limit the rotation of the dog 19 and latch 23 in either direction.

I claim:

1. A release device for a chain hoist having a lift chain, said device comprising frame members, a hook adapted to engage said chain pivoted to said frame member, said hook whenreleased being adapted to swing about its pivot to chain-releasing position, a retractable latch engaging said hook to hold the same in load-carrying position, a guide secured to said frame member having a surface over which a portion of said chain passes after passing around a load, said surface being shaped to guide said chain as it passes thereover, a pivotally mounted pawl engageable with the chain on said surface, a coiled spring having one end connected to said pawl for holding the same in load carrying position and adapted to permit retraction of said pawl for tightening of said chain around the load and the other end connected to said latch for holding said latch and said hook in load carrying position and adapted to permit retraction of said latch for releasing said load, said hook, said pawl and said latch all being disposed in longitudinal alignment with respect to each other.

2. A release device for a chain hoist having a lift chain, said device comprising frame members, a hook adapted to engage said chain pivoted to said frame members, said book when released being adapted to swing about its pivot to chain-releasing position, a guide secured to said frame members having a surface over which a portion of said chain passes after passing around a load, said surface being shaped to guide said chain as it passes thereover, a pivotally mounted pawl engageable with the said chain on said surface and adapted to be automatically retracted for the tightening of said chain around the load, a latch pivoted to said frame members and adapted to engage said hook to hold the same in load-carrying position, a coiled spring having one end connected to said latch and the other end thereof connected to said pawl for normally holding said latch in latching engagement with said hook and said pawl in engagement with said chain, a trip member insertable in said frame member in a position to engage said latch, said hook, said pawl and said latch all being disposed in longitudinal alignment with respect to each other, means including a trip cord connected to said trip member and adapted to actuate the same, and guide means carried by said frame members to guide said trip member when so actuated in a path to engage and retract said latch.

3. A release device for a chain hoist having a lift chain, said device comprising frame members, a hook adapted to engage said chain pivoted to said frame members, said hook when released being adapted to swing about its pivot to chain-releasing position, a guide secured to said frame members having a surface over which a portion of said chain passes after passing around a load, said surface being shaped to guide said chain as it passes thereover, a pivotally mounted pawl engageable with the said chain on said surface and adapted to be automatically retracted for the tightening of said chain around the load, a latch pivoted to said frame members and adapted to engage said hook to hold the same in loadcarrying position, a coiled spring having one end connected to said latch and the other end thereof connected to said pawl for normally holding said latch in latching engagement with said hook and said pawl in engagement with said chain, said hook, said pawl and said latch all being disposed in longitudinal alignment with respect to each other, said frame members having aligned slots disposed to guide a trip member in a path to engage and retract said latch and a trip member having a pair of spring arms extendable along the sides of said frame members and having inturned ends extending through said slots and engageable with said latch, and means including a trip cord connected to said trip member and adapted to actuate the same for retracting said latch and thereby releasing the load.

4. A release device for a chain hoist having a lift chain, said device comprising frame members, a hook adapted to engage said chain pivoted to said frame members, said hook when released being adapted to swing about its pivot to chain-releasing position, a guide secured to said frame members having a surface over which a portion of said chain passes after passing around a load, said surface being shaped to guide said chain as it passes thereover, a pivotally mounted pawl engageable with the said chain on said surface and adapted to be automatically retracted for the tightening of said chain around the load, a latch pivoted to said frame members and adapted to engage said hook to hold the same in load-carrying position, a coiled spring having one end connected to said latch and the other end thereof connected to said pawl for normally holding said latch in latching engagement with said hook and said pawl in engagement with said chain, said hook, said pawl and said latch all being disposed in longitudinal alignment with respect to each other, said latch having a bifurcated end portion forming a longitudinal slot, said frame members having aligned grooves disposed to guide a trip member in a path to engage and retract said latch and a trip member comprising a pair of spring arms having vertical portions extending through said slot and having horizontal end portions extending into said grooves and engageable with said latch, and means including a trip cord connected to said trip member and adapted to actuate the same for retracting said latch and thereby releasing the load.

References Cited in the file of this patent UNITED STATES PATENTS 1,181,000 Gregg Apr. 25, 1916 1,224,148 Crosby May 1, 1917 1,963,634 Stahl et a1. June 19, 1934 

